The provisions in question give law enforcement access to troves of personal information, including business and library records, if a judge approves. They also permit roving wiretaps on terrorism suspects who change numbers, and allow surveillance of foreign terrorism suspects who appear unaffiliated with known groups such as al Qaeda.

The Patriot Act was first passed in October 2001 to give authorities expanded powers to investigate suspected terrorists. Parts of the law were made permanent in 2006, but the three provisions now being discussed in Congress will expire Feb. 28 if nothing is done to extend them.

Last Monday, 26 Republicans, including eight newly elected lawmakers, voted against the extension measure, citing concerns over civil liberties and a lack of information about the law. That vote was conducted under House rules that require a two-thirds majority, and fell seven votes short of passage. This week, Republican leaders brought the bill up under rules that require only a simple majority. The voting was similar, with 27 Republican lawmakers voting "nay."

Most Democrats voted against the measure both times. In Monday's vote, 65 Democrats voted yes.

"We should not extend these provisions for…any period of time," said Rep. Bobby Scott (D., Va.). "I do not accept the argument that in order to be safe we have to necessarily sacrifice our rights and freedoms."

Mr. Sensenbrenner, who wants to make the law permanent, plans to hold hearings during the next 10 months to determine if the law needs more oversight.

In the Senate, where Democrats retain a slim majority, two bills from Democrats would extend the provisions for nearly three years. A third from Republicans would make them permanent. Some Senate Democrats want to add more oversight provisions before extending the law.

President Barack Obama, a past critic of the Patriot Act, believes lawmakers should extend the surveillance powers until December 2013, according to a White House policy statement released last week.